compression, deck height, rod - piston combo - help..
Thread Starter
Teching In
Joined: Jul 2010
Posts: 36
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From: Orlando, Fl
compression, deck height, rod - piston combo - help.. Ok guys, don't be to hard on me.
this is my first engine build and I think I may have made a mistake.
I have a 5.3 with stock crank. Stock deck height on block. Choice of power is turbo.
now the stock rod piston combo was out of the question as they were in bad shape when I got the motor.
So, I purchased wiseco 5.3 junkyard dog -10.7cc pistons.
When it came to rods, almost all replacements I found were 6.125". And I read people had no issue with them.
I have searched for an answer to my question but nothing exact.
I believe I calculated deck height correctly at 0.017 out of the hole.
Did I kill the compression drop of the -10.7cc. and raise compression back up with these rods? or how does that work?
The pistons say compression is 9.0:1 with 6.098 rod. which is a deck height of -0.010. I believe.
Do I just get a thinker gasket to make up for the difference or What do I do?
Pretty much any info will help.
this is my first engine build and I think I may have made a mistake.
I have a 5.3 with stock crank. Stock deck height on block. Choice of power is turbo.
now the stock rod piston combo was out of the question as they were in bad shape when I got the motor.
So, I purchased wiseco 5.3 junkyard dog -10.7cc pistons.
When it came to rods, almost all replacements I found were 6.125". And I read people had no issue with them.
I have searched for an answer to my question but nothing exact.
I believe I calculated deck height correctly at 0.017 out of the hole.
Did I kill the compression drop of the -10.7cc. and raise compression back up with these rods? or how does that work?
The pistons say compression is 9.0:1 with 6.098 rod. which is a deck height of -0.010. I believe.
Do I just get a thinker gasket to make up for the difference or What do I do?
Pretty much any info will help.
assuming wrist pin height is the same, yes. With the longer rod, you raise the piston surface higher in the bore. In this case, it would be raised by .027", which isn't all that much. I'd say just get a thicker gasket and let 'er eat 
Thread Starter
Teching In
Joined: Jul 2010
Posts: 36
Likes: 0
From: Orlando, Fl
ok well after more research and calculation.
I have figured right around 9.15:1 compression.
Thanks for the response, its reassuring.
I'm thinking .061 gasket will do the trick.
what do yall think?
I have figured right around 9.15:1 compression.
Thanks for the response, its reassuring.
I'm thinking .061 gasket will do the trick.
what do yall think?
Btw, there are plenty of 6.100" rods available. Scat and Eagle make cheaper 6.100" rods and Compstar makes a nice rod at 6.100" available for a .947" wrist pin (which I assume the Junkyard dogs use).
Either way, just grab some Cometics .060" and let her rip. I think 9.5:1-9.8:1 is better on boost anyway.
Either way, just grab some Cometics .060" and let her rip. I think 9.5:1-9.8:1 is better on boost anyway.
